In recent years, roller skating and in-line skating have become extremely popular. Many participants in these sports have developed an interest in what is known as "aggressive" or "extreme" skating. Such skating includes jumping, flipping, sliding across raised surfaces, sliding down rails, and other similar types of maneuvers.
Skates generally have a frame and a boot coupled to the frame. The boots of many in-line skates include hard outer shells covering portions of a soft inner liner. Typically, the frame of a skate is made of plastic or metal and has a platform with an upper surface and a lower surface. The platform generally has a toe area and a heel area, with the heel area being vertically higher than the toe area. The boot has a sole and is positioned with the sole abutting the upper surface of the frame platform. The boot is typically attached to the frame by rivets that extend through the toe areas of the sole of the boot and the frame platform and through the heel areas of the sole of the boot and the frame platform.
Wheels are attached to a lower portion of the frame. Generally, the lower portion of the frame includes inner and outer elongated parallel rails each being longitudinally connected to the lower surface of the platform and aligned along a center portion of the platform such that the platform forms oppositely disposed inner and outer lateral flanges. The inner lateral flange extends outwardly from the inner rail and the outer lateral flange extends outwardly from the outer rail.
In one example of aggressive or extreme skating maneuvers, the outer rail and the lower surface of the outer lateral flange of the platform are used to slide or grind along raised surfaces such as, for example, concrete walls, metal rails and the like. The attached boot and its shell may also be used to slide or grind along raised surfaces and rails. In another type of extreme skating, a skater may jump onto a metal rail such that the longitudinal axis of the skate frame is transverse to the rail, with a portion of a bottom edge of the skate frame engaging the rail. Typically, skaters grind on a portion of the skate frame bottom edge, which is disposed between two middle wheels of a four-wheeled skate.
Some aggressive skates utilize what is known in the industry as an H-block. An H-block is typically a substantially square or rectangular block made of plastic. It is inserted between the longitudinal rails of the frame and is disposed between the two middle wheels. Generally, H-blocks are connected to the frame by a bolt or rivet which extends through the H-block and the inner and outer rails with a head of one end of the bolt abutting the outer side of one rail and a nut or other clamping device securing an opposite end of the bolt and abutting the outer side of the other rail.
As a skater builds momentum and lands on the rail as previously described, the portion of the skate frame bottom edge between the two middle wheels and an adjacent bottom side of the H-block will engage and slide along the rail. This type of sliding or grinding wears away the bottom edge of the skate frame and wears away the H-block to form a concave groove which enhances stability for grinding or sliding in this manner. Many skaters choose to purposely form a groove in this area of the skate frame and H-block to facilitate sliding or grinding on rails. Generally, new skates will have a flat bottom edge of the frame and an adjacent flat side of the H-block. Skaters often will use an abrasive surface or material to rub in this area to form a groove before trying to grind or slide across rails on this area of the skate.
A common problem with the prior art embodiments of H-blocks typically occurs when skaters are sliding or grinding on the lower surface of frame platform. If a skater is grinding along a frame platform, the outer side of the adjacent longitudinal rail often comes into contact with the surface upon which the skater is sliding. The head or nut of the bolt holding the H-block in place quickly wears away as it slides across an abrasive surface such as metal or concrete. Thus, H-blocks frequently come loose and skaters have to replace the bolts to maintain the stability of their H-blocks.
In aggressive or extreme skating, it is desirable to have a skate that evenly distributes forces upon the skate such that the skater experiences as smooth a transition as possible when landing from a jump. Generally, boots are attached to skate frames by two bolts or rivets, one in the toe area and one in the heel area. Thus, there is often a gap between the sole of the boot and the frame in the intermediate portion between the toe and heel areas. In addition, the typical two bolt toe and heel attachment of the boot to the frame is provided between substantially flat toe and heel portions of a sole and substantially flat toe and heel portions of a frame platform, respectively. In this type of skate, energy transfer from the skate frame to the boot is substantially perpendicular to the boot and is concentrated in the toe and heel areas. Thus, the skater may experience extreme loads under the toe and heel areas of the sole of the foot during aggressive skating maneuvers. In addition, concentrated loads produced on the toe and heel areas of the boot may affect stability of the skate when the toe and heel areas are flat and bolted to substantially flat toe and heel areas of a skate platform.
Other aggressive skate embodiments help accommodate stability but do not significantly enhance energy transfer from the frame to the skate. Such embodiments include rectangular or square projections from the toe and heel portions of the sole of the boot into corresponding rectangular or square recesses in the toe and heel portions of the platform of the frame. Consequently, the connection mechanism between the boot and the frame of a skate for aggressive skates needs to provide more stability and facilitate more even distribution of loads from the frame to the boot.
Other features desired by aggressive skaters include a low frame stance, rockering ability, and the ability to replace the inner two wheels with wheels that are smaller than the outer two wheels while maintaining ground contact with all of the wheels. Typically, in-line skates use eccentric spacers to adjust the positioning of the various wheels. One example of an eccentric spacer is disclosed in commonly assigned U.S. Pat. No. 5,048,848. One desirable feature of an eccentric spacer is to maintain a low frame stance with various wheel sizes. It is also desirable for eccentric spacers to be configured to permit a skater to use a larger diameter wheel in the front and the back of the skate and to use a smaller diameter wheel in the middle two wheel positions of the frame while maintaining ground contact with all of the wheels. Smaller wheels in the middle two positions are desirable because they provide a greater distance between the wheels in the middle of the frame for grinding.
It is also desirable to have a spacer that permits rockering. Rockering is a term used to indicate that the lowest circumferential points of the front most and the rear most wheels are vertically higher from the ground than the lowest circumferential points of the wheels between the front most and rear most wheels of the skate. Thus a curved plane of ground contact is formed to permit "rockering" by the skater. Currently, eccentric spacers do not offer the combination of low frame stance for different sized wheels, rockering ability, and the ability to replace the inner two wheels with wheels that are smaller than the outer two wheels while maintaining ground contact with all of the wheels.
Another desirable feature of in-line skates for aggressive skating is a pivoting cuff with a limited range of lateral movement by the cuff relative to the shell. Skaters often bend their legs and consequently put lateral stress on the cuff against the shell. A skate that does not permit any lateral movement can feel too rigid to the skater. Also, some current skates on the market provide small slots at the pivoting connection of the cuff and the lower shell to permit such movement. However, this design is not suitable because the slot permits lateral movement without any bias to bring the cuff to its normal position after the skater has finished bending.
The present invention provides a solution to these and other problems and offers other advantages over the prior art, as will be understood with reference to the summary, the detailed description and the drawings.